This invention relates to a developing device that develops a latent image formed on a photosensitive body using a developer. This invention also relates to a developer storing container and a developing unit used in the developing device, and an image forming apparatus employing the developing device.
A conventional toner cartridge includes an outer cartridge that stores the toner therein and has a toner supply opening. The conventional toner cartridge also includes a shutter provided to open and close the toner supply opening of the outer cartridge. The shutter is configured to close the toner supply opening via a sealing sponge when the shutter is in a closing position. When the toner cartridge is mounted to the developing unit and when the toner supply opening is to be opened, the shutter is moved to an opening position where an opening formed on the shutter is aligned with the toner supply opening of the outer cartridge to thereby supply the toner to the developing unit (see, for example, Patent Document No. 1).
Patent Document No. 1: Japanese Laid-Open Patent Publication No. 2006-243446 (Page 6, FIG. 1).
However, in the above described conventional toner cartridge, the toner may adhere to the surface of the sealing sponge of the shutter and to a circumference of the toner supply opening of the outer cartridge. In such a case, when the toner cartridge is detached from the developing unit, the toner may be scattered and may contaminate the surroundings.